The shop uses an Axi-Line driveshaft machine to press driveshaft components together, and then check trueness and balance of the 'shafts it builds. This dynamic balancer helps the builder determine where to add welded weights to the driveshaft to get it to spin without vibration. Here one of the builders is balancing a truck driveshaft. Washer-like weights are welded to the driveshaft once the balancer and operator determine the correct location.